Gaseous fuels, such as butane and propane, have found a wide acceptance in household and/or recreational vehicle use. Such fuels are commonly used in association with gas grills, gas lamps, gas heaters, gas cutting torches, and other similar devices. When using such devices, an individual obtains a pressurized gas vessel or cylinder and then connects the vessel or cylinder to a gas consuming device. Typically, the gas consuming device operates at a pressure less than the gas pressure in the pressurized gas vessel or cylinder. As a result, a pressure regulator is mounted downstream of the valve on the pressurized gas vessel or cylinder to reduce the pressure of gas flowing through the valve and into the gas consuming device.
Presently, various safety regulations exist concerning the operation of the valve on the pressurized gas vessel or cylinder. As a result, several attempts have been made to minimize the escape or loss of gas when a gas consuming device is connected to and/or disconnected from the pressurized gas vessel or cylinder. In addition, gas escape or loss also occurs during the refilling of the gas vessel or cylinder. The most common cylinder valve insert is disclosed in U.S. Pat. No. 5,330,155 to Lechner, issued on Jul. 19, 1994. Another cylinder valve insert is disclosed in U.S. Pat. No. 5,553,638 to Home, issued on Sep. 10, 1996. Still another cylinder valve insert is disclosed in U.S. Pat. No. 5,582,201 to Lee, issued on Dec. 10, 1996. These three patents are incorporated herein by reference. These three cylinder valve inserts reduce the amount of gas escape or loss when a male connector is connected to the valve on the gas vessel or cylinder. However, these valve inserts still result in some gas escape or loss, especially after a male connector has been connected and disconnected several times from the gas vessel or cylinder.
The valve inserts of Lechner ""155, Home ""638 and Lee ""201 are designed to be mounted to a standard cylinder valve. Each valve insert includes a tubular body a valve member and a seal mounted to the valve member. The valve member includes a docking member designed to form a seal with a nipple of a standard connection fitting. The valve member is biased by a valve member spring, thereby causing the valve member to resist movement when the nipple contacts the docking member. The valve member laterally moves in the tubular body as the nipple is further inserted into the tubular body. The lateral movement of the valve member causes the seal to move from a closed to an opened position, thereby allowing gas to flow between the connection fitting and the cylinder valve.
Home ""638 is directed to an improvement over Lechner ""155. Home ""638 discloses a tubular member having L-shaped notches designed to mate with a wrench. The L-shaped notches are designed to simplify the insertion of the tubular body into cylinder valve. Home ""638 also discloses that the valve member includes an abutment surface for engagement with a modified POL nipple. The modified POL nipple engages the docking member on the valve member in a manner to reduce gas from leaking between the POL nipple and the valve member. Home ""638 discloses that the modifications to the valve member and the POL nipple overcome a problem associated with the valve insert disclosed in Lechner""155. Home ""638 discloses that, after repeated use of the Lechner valve insert, the strength of the spring may weaken, resulting in the POL nipple not hermetically engaging the docking member prior to the seal moving to an opened position.
Although the arrangement disclosed in Home ""638 may overcome a design shortcoming of Lechner ""155, the redesigned valve member of Home ""638 has its own shortcomings. The modified POL nipple is designed to contact and to abut a surface on the valve member to cause the valve member to move laterally. Prior to the valve moving, the contoured surfaces of the POL nipple form a seal with the docking member on the valve member. However, after continued use, the docking member will become compressed and/or become worn in certain regions. As a result, the end of the POL nipple will abut against the valve member and cause the seal to open prior to the POL nipple forming a seal with the docking member on the valve member, thereby resulting in gas escaping from the cylinder valve.
Lee ""201 discloses a valve insert that is similar to the valve insert of Lechner ""155 and Home ""638. The valve insert has a spring positioned on the end of the seal instead of between the tubular body and valve member as shown in Lechner ""155 and Home ""638. Similar to the problems associated with the valve inserts of Lechner ""155 and Home ""638, after continued use, the docking member will become compressed and/or become worn in certain regions thereby, resulting in the seal being moved to the opened position prior to the POL nipple forming a seal with the docking member on the valve member.
In view of the disadvantages of present valve inserts, there is a continued demand for a valve insert that ensures adequate sealing with a separable male connection, and that will minimize the loss or escape of gaseous fuel when the cylinder is disconnected from and re-connected to the male connection.
The present invention is related to the field of valves, and more particularly to an improved insert which is adapted to be mounted to the outlet end of a cylinder valve to improve the sealing engagement with a separable male fitting. The invention is particularly directed to LPG cylinder valves for household and recreational vehicle use, and will be particularly described with reference thereto. However, the invention has broader applications and can be used in any type of fluid valve wherein the prevention of leaking or escaping fluid (e.g. gas and/or liquid) is desired. For instance, the improved insert can also be used in industrial applications (e.g., welding gas cylinders, oxygen cylinders for medical applications, shielding gas cylinders for welding, helium gas cylinders used to inflate objects, hydrogen fuel tanks, etc.).
In accordance with one aspect of the present invention, a cylinder valve such as, but not limited to, a LPG cylinder valve, includes a valve insert designed to reduce or prevent leakage of fluid from the cylinder valve when a fluid connector is connected to and/or disconnected from the cylinder valve. The valve insert can be removably or irremovably inserted in the cylinder valve. When the valve insert is removably inserted in the cylinder valve, the valve insert can be connected to the cylinder valve in a variety of manners such as, but not limited to, a threaded arrangement, a snap ring arrangement, a bolt or screw arrangement, a latch arrangement, spring clip arrangement, a clamp arrangement, and/or the like. When the valve insert is irremovably inserted in the cylinder valve, the valve insert can also or alternatively be connected to the cylinder valve in a variety of manners such as, but not limited to, gluing, welding, brazing, soldering, riveting and/or the like. Alternatively, the interior of the cylinder valve can be configured by molding, machining, or the like to integrally form one or more components of the valve insert in the cylinder valve.
In accordance with another and/or alternative aspect of the present invention, the valve insert is mounted as a unit on and/or in a cylinder valve outlet to selectively enable a flow of fluid therethrough when another fluid connector is sufficiently engaged therewith, and to substantially prevent such fluid flow,when the cylinder valve and the fluid connector are sufficiently separated from one another. The valve insert includes a body member, a valve member, a seal member, and a valve biasing member. The components of the valve insert can be made from a variety of materials such as, but not limited to, metal, ceramic, plastic and/or rubber (natural and/or synthetic). In one embodiment of the invention, the body member is adapted to be sealingly connected to the cylinder valve. In one aspect of this embodiment, the body member has a generally tubular or cylindrical shape having an outwardly-facing surface that engages the inner surface of the cylinder valve; however, the body member can have other shapes. In another and/or alternative aspect of this embodiment, the inner surface of the cylinder valve includes a threaded surface, and the outwardly-facing surface of the body member includes a threaded surface to enable the body member to be at least partially threaded in the cylinder valve. In still another and/or alternative aspect of this embodiment, the body member is fully inserted in the cylinder valve. In yet another and/or alternative aspect of this embodiment, only a portion of the body member is inserted in the cylinder valve. In another and/or alternative embodiment of the invention, the body member has an opening to allow fluid to flow therethrough. In still another and/or alternative embodiment of the invention, the body member has a seal seat facing toward the direction of fluid flow. In yet another and/or alternative embodiment of the invention, the body member has an abutment surface facing away from the direction of fluid flow. In a further and/or alternative embodiment of the invention, the body member has an inwardly-facing surface designed to at least partially contain one or more other components of the valve insert. In yet a further and/or alternative embodiment of the invention, the valve member is at least partially positioned in the body member for at least partial movement relative therein. In another and/or alterative embodiment of the invention, the front of the valve member includes a docking member adapted to engage a portion of the fluid connector. In one aspect of this embodiment, the fluid connector includes a POL nipple that at least partially engages the docking member as the fluid connector is connected to the cylinder valve. In still another and/or alternative embodiment of the invention, the rear of the valve member includes a seal contact surface. In yet another and/or alternative embodiment of the invention, the valve member includes an abutment surface that faces the body member abutment surface when the valve member is positioned in the body member. In yet another and/or alternative embodiment of the invention, the valve member includes an outwardly-facing surface configured to slidably engage the body member inwardly-facing surface. In another and/or alternative embodiment of the invention, the seal member is adapted to at least partially form a fluid seal with the seal seat of the body member. In one aspect of this embodiment, the seal member inhibits or prevents fluid from flowing through the valve insert when the seal member abuts against the seal seat. When the seal member moves away from the seal seat, the seal formed by the sealing member is broken to allow fluid to flow through the valve insert. In another and/or alternative aspect of this embodiment, the size of the fluid channel or orifice opening between the seal seat and the seal member is at least partially a function of the distance the seal member is positioned from the seal seat. In still yet another and/or alternative embodiment of the invention, the seal member moves independently from the valve member. In a further and/or alternative embodiment of the invention, the seal member is at least partially connected to the valve member. In still a further and/or alternative embodiment of the invention, the seal member includes an at least partially compressible material. In one aspect of this embodiment, the compressible part of the seal member is made of rubber and/or plastic having a hardness of at least about 50 durometer on a Shore xe2x80x9cAxe2x80x9d scale. In one particular design, the seal member has a hardness of about 85-95 durometer on a Shore xe2x80x9cAxe2x80x9d scale. In another and/or alternative embodiment of the invention, the seal contact surface of the valve member is at least partially designed to contact at least a portion of the seal member to cause the seal member to move away from the seal seat of the body member. In still another and/or alternative embodiment of the invention, the valve biasing member exerts a biasing force between the body member and valve member abutment surface. In one aspect of this embodiment, the valve biasing member causes the valve member to be continuously urged to move toward the front of the valve insert. In one particular design, such urging results in the seal contact surface of the valve member to be urged away from the seal member. In yet another and/or alternative embodiment of the invention, the valve biasing member includes a variety of members such as, but not limited to, one or more springs, an elastic material, a compressible material, a resilient material, fluid piston, shape memory alloy, and/or the like. In still another and/or alternative embodiment of the invention, the valve biasing member includes a compressible fluid.
In accordance with still another and/or alternative aspect of the present invention, the valve insert includes one or more sealing members to inhibit or prevent fluid leaks through the valve insert and/or to prevent foreign materials from interfering with the operation of one or more components of the valve insert. The sealing members can be a variety of different components such as, but not limited to, sealing rings, wiper seals, sealing fluids, gaskets, compressible inserts, and/or the like. Various types of sealing rings can be used such as, but not limited to, O-rings, quad rings, and/or the like. The sealing members can be made of a variety of materials such as, but not limited to, rubber and/or plastic. The hardness and/or durability of the sealing members can be same or different from one another, when two or more sealing members are used. Generally, the hardness of the sealing members is at least about 30-40 durometer on a Shore xe2x80x9cAxe2x80x9d scale. Typically, the hardness of the sealing members is at least about 50 durometer on a Shore xe2x80x9cAxe2x80x9d scale; however, other durometer values can be used. In one embodiment of the invention, the surfaces between the body member and the valve member include one or more sealing members. In one aspect of this embodiment, the surfaces between the body member and the valve member include at least one sealing ring. In another and/or alternative aspect of this embodiment, the surfaces between the body member and the valve member include a lubricant that at least partially functions as a sealing fluid. The lubricant can also facilitate in non-sticking movement of the surfaces of the body member and the valve member. In still another and/or alternative aspect of this embodiment, the surfaces between the body member and the valve member include at least one sealing ring and a lubricant. The lubricant facilitates in non-sticking movement of the surfaces of the body member and the valve member, and/or the surfaces of the body member and/or valve member over and/or about the sealing ring. In one particular configuration of this aspect, at least one sealing ring is a quad seal ring. The design of the quad seal ring allows for lubricant to be at least partially maintained between the cavities of the quad seal ring, thereby continuously lubricating the surfaces between the body member and/or the valve member when the valve member moves. In another and/or alternative particular configuration of this aspect, the quad seal ring has a four lobed cross-sectional shape which includes a recess between two adjacent lobes. A lubricant, if used, is typically applied to the surfaces of the quad seal ring. The recesses of the quad seal ring trap a portion of the lubricant, thereby lubricating the surfaces facing the body member and the valve member each time the valve member moves within the body member. The lubricated surfaces inhibit or prevent sticking of the valve member in the body member. In still another and/or alternative aspect of this embodiment, at least one sealing member is affixed to the valve member so as to move with the valve member. In still yet another and/or alternative aspect of this embodiment, at least one sealing member is affixed to the body member so as to remain substantially stationary when the valve member moves within the body member. In a further and/or alternative aspect of this embodiment, the surfaces between the body member and the valve member include at least two sealing members which are spaced apart. In one particular configuration of this aspect, the at least two sealing members include a sealing ring, wiper seal, and/or the like. In one specific design of this configuration, the surfaces between the body member and the valve member include a sealing ring and a wiper seal. The sealing ring and wiper seal can be affixed to the valve member and/or the body member. It is not necessary for both the sealing ring and wiper seal to be affixed to the same member. The combination sealing ring and wiper seal facilitates in limiting the amount of foreign material that deposits between the valve member and the body member. The combination sealing ring and wiper seal also facilitates in maintaining lubricant, if used, between the sealing ring and/or the wiper seal. In another and/or alternative specific design of this configuration, the wiper ring includes a nub that is at least partially adapted to contact one or moving surfaces of the valve member. In still another and/or alternative specific design of this configuration, the wiper ring is inserted at or closely adjacent to the front end of the body member. In yet another and/or alternative specific design of this configuration, the wiper ring is vulcanized to the body member; however, the wiper ring can be attached to the body member or valve member in other manners. The wiper ring inhibits or prevents foreign materials from settling between the valve member and the body member to inhibit or prevent sticking of the valve member or inhibit or prevent restriction of movement of the valve member within the body member. The wiper ring also or alternatively facilities in removing foreign material that has settled between the valve member and the body member when the valve member moves within the body member. The wiper ring further or alternatively inhibits or prevents lubricant from escaping between the wiper ring and the quad seal ring, thereby facilitating in ensuring proper and continued lubrication.
In accordance with yet another and/or alternative aspect of the present invention, the valve insert includes a seal biasing member. The seal biasing member at least partially causes the seal member to be urged toward the seal seat of the body member. In one embodiment of the invention, the seal biasing member causes the seal member to move toward the seal seat of the body member and into the closed position when the fluid connector is not connected to the fluid valve. The seal biasing member can include a variety of members such as, but not limited to, one or more springs, an elastic material, a compressible material, a resilient material, fluid piston, shape memory alloy, and/or the like. In another and/or alternative embodiment of the invention, the seal biasing member is positioned in the cylinder valve such that the seal biasing member is at least partially compressed between the seal member and at least one surface of the cylinder valve. In still another and/or alternative embodiment, the seal biasing member is at least partially connected to the seal member and/or the cylinder valve. In yet another and/or alternative embodiment of the invention, the seal biasing member continuously urges the seal member toward the seal seat of the body member.
In accordance with yet another and/or alternative aspect of the present invention, at least a portion of the valve member travels a distance in the body member prior to the seal contact surface of the valve member contacting the seal member. This valve member and seal member arrangement facilitates in the formation of a sealing engagement between the valve member and the fluid connector prior to moving the seal member away from the seal seat of the body member. In one embodiment of the invention, the docking arrangement on the valve member includes one or more sealing arrangements to form a sealing engagement with at least portion of the fluid connector. In one aspect of this embodiment, the fluid connector includes a POL nipple. The front and/or sides of the POL nipple contact the docking member, resulting in the one or more sealing arrangements on the docking member at least partially forming a seal with the POL nipple as the fluid connector is connected to the cylinder valve. The one or more sealing arrangements can include a variety of materials such as, but not limited to, rubber and/or plastic. Generally, at least a portion of the one or more sealing arrangements is compressible. The valve biasing member causes the valve member to resist movement in the body member as the fluid connector is forced into contact with the docking member of the valve member. When the fluid connector includes a POL nipple, the POL nipple typically engages the docking member of the valve member. The countering force of the valve biasing member at least partially causes a sealing engagement to be formed and maintained between the fluid connector and the docking member prior to the seal contact surface of the valve member causing the seal member to be moved off the seal seat of the body member. As can be appreciated, even after the docking member becomes worn after the fluid connector has been repeatedly connected and disconnected from the cylinder valve, the biased valve member, in combination with the travel distance of the valve member prior to contacting the seal member, facilitates in ensuring that a sealing engagement is formed between the docking member on the valve member and the fluid connector prior to the movement of the seal member being moved to opened position by the seal contact surface of the valve member. The sealing engagement between the docking member of the valve member and the fluid connector ia further ensured by the pressure of the fluid acting on the seal member and urging the seal member to remain in the closed position. This added force requires at least a portion of the fluid connector to further be engaged with the docking member to overcome this fluid force. When a seal biasing member is used in the valve insert, the seal biasing member also continuously resists the seal member being moved off the seal seat of the body member to an opened position. This added force by the seal biasing member further ensures that a sealing engagement is maintained between the docking member and fluid connector while the seal member is in an opened position.
In accordance with a further and/or alternative aspect of the present invention, the valve insert is designed such that when the seal member is moved off the seal seat of the body member and to an opened position, a pressure differential across the valve will cause a tighter sealing engagement to form between the docking member and the fluid connector.
In accordance with yet a further and/or alternative aspect of the present invention, the cylinder valve includes a coupling arrangement to secure a fluid connector to the cylinder valve. In one embodiment of the invention, the outer surface of the cylinder valve includes a threaded section that allows the fluid connector to be threaded to the cylinder valve. In another and/or alternative embodiment of the invention, the coupling arrangement and the fluid connection form at least a partial seal prior to the sealing member moving off the seal seat of the body member to an open position, and/or after the sealing member has moved back onto the seal seat to a closed position. The partial seal limits or prevents fluid from escaping even if a fill sealing arrangement between the nipple of the fluid connector and docking member is not fully formed. In still another and/or alternative embodiment of the invention, the coupling arrangement includes one or more sealing arrangements.
The principal object of the present invention is to provide an insert for a cylinder valve which reduces the leakage or escape of gas when a fluid connector is connected to and/or disconnected from the cylinder valve.
Another and/or alternative objective of the present invention is to provide a valve insert that is simple to use and has a longer use-life.
Still another and/or alternative objective of the present invention is to provide a valve insert that insures adequate sealing with a separable male connection.
Yet another and/or alternative objective of the present invention is to provide a valve insert that minimizes the loss or escape of gaseous fuel when the cylinder is disconnected and reconnected to the male connection.
Still yet another and/or alternative objective of the present invention is to provide a valve insert that can be used with existing cylinder valve designs.
A further and/or alternative objective of the present invention is to provide a valve insert that can be used on LPG cylinder valves.
Still a further and/or alternative objective of the present invention is to provide a valve insert that can be removably inserted in a cylinder valve.
Still yet a further and/or alternative objective of the present invention is to provide a valve insert that can form a seal with a male connector having a POL nipple.
Another and/or alternative objective of the present invention is to provide a valve insert that can form a seal with a male connector and travels a distance prior to allowing a fluid to pass through the valve insert.
Still another and/or alternative objective of the present invention is to provide a valve insert that is biased in a closed position.
Yet another and/or alternative objective of the present invention is to provide a valve insert that forms a tighter sealing arrangement with a fluid connector due to a pressure differential across the valve insert when the valve insert is in an opened position.
Still yet another and/or alternative objective of the present invention is to provide a valve insert that is simple and cost effective to manufacture.